fbdev/hyperv_fb: deprecate this in favor of Hyper-V DRM driver

fbdev/hyperv_fb: deprecate this in favor of Hyper-V DRM driver

The Hyper-V DRM driver is available since kernel version 5.14 and it
provides full KMS support and fbdev emulation via the DRM fbdev helpers.
Deprecate this driver in favor of Hyper-V DRM driver.

Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>